A basic tool of the general type on which the present invention affords an improvement forms the subject matter of the U.S. Pat. No. 4,771,833 to Thomas S. Honsa. The tool there is of the so-called pistol-grip type having a handle including a forwardly opening barrel within which a cup-like member is disposed in concentric fashion so as to provide annular space between the exterior of the cup and the interior of the barrel, which space is filled with elastomer shock-absorbing material. A significant improvement according to the present invention is that the elastomer material is in laminar form, thus further minimizing tool-generated vibrations and thus further isolating the user from tool-generated forces, all leading to material reduction in operator fatigue, especially from conditions creating carpal tunnel syndrome, the characteristic of which is that tendons passing through the narrow channel in the wrist, called the carpal tunnel, are over-used and press on the median nerve that controls feeling in the hand. The disorder is extremely painful and can be permanent. Other disorders includes "vibration white finger" and Raynaud's phenomena.
A further feature of the invention is the provision of structure for centering the cup within the handle cavity in preparation for the introduction of the elastomer material. In this respect, the structure is such that it can remain within the tool without adverse effects on the operation of the tool. An added feature of the invention is the provision of elastomer and further of different dimensions. In a fluid-powered tool, the invention provides improved internal passage means for communication with external fluid-conducting means.
The foregoing and other features will become apparent as a preferred embodiment of the invention is disclosed in detail in the ensuing specification and accompanying sheets of drawings.